Z Her

References

1. Tumer1984
   Tumer, O., Ibanoglu, C., Tunca, Z. & Evren, S. “Light-curve Analysis of Z Herculis”: 1984, Astrophysics & Space Science, Volume 102, pp. 225-244
   http://adsabs.harvard.edu/cgi-bin/nph-bib_query?bibcode=1984Ap%26SS.104..225T&db_key=AST&high=3f567b0b2c12820

2. Popper1988
   Popper, Daniel M. “Orbits of Close Binaries with Ca II H and K in Emission. I - Z Herculis and RS Canum Venaticorum”: 1988, The Astronomical Journal, Volume 95, pp. 1242-1250
   http://adsabs.harvard.edu/cgi-bin/nph-bib_query?bibcode=1988AJ.....95.1242P&db_key=AST&high=3f567b0b2c12627